23 Myths of Differentiated Instruction

“Differentiation is simply a teacher attending to the learning needs of a particular student or small groups of students, rather than teaching a class as though all individuals in it were basically alike.”—Carol Ann Tomlinson (2000)

Most advocates of differentiated instruction (DI) would certainly agree with Carol’s definition. However, educators who venture much beyond that simple statement may quickly part paths with their colleagues regarding how best to accomplish that mission in the classroom. DI is certainly not an easily-identified, monolithic movement. Indeed, the movement is multi-faceted. There is no DI uniform.

Educational organizations, publishers, researchers, and presenters have jumped on the DI bandwagon over the last dozen years and DI is now big business. Everyone tends to define DI in ways that best suit their pedagogical presuppositions and/or interests. However, the basic principles of DI cannot be co-opted by any group because DI is fundamentally just good teaching.

With Response to Intervention (RTI) now taking center stage throughout many school districts today, it is increasingly important to shed light on some of the key myths of DI. Teachers who have resisted implementing DI because of these myths may be encouraged to re-visit how they teach their students.

Educational Philosophy

1.Contrary to popular belief, differentiated instruction has not been completely kidnapped by constructivists. Constructivism is an educational philosophy predicated on the belief that learning occurs best when students construct their own “rules,” “mental models,” and “meaning-making” to integrate new experiences into their existing schemata and prior knowledge. As applied to differentiated instruction, constructivists including the likes of Carol Ann Tomlinson, Amy Benjamin, and Rick Wormeli, believe that students should be provided multiple options for taking in information and making sense of ideas and that teachers must adapt the curriculum or mode of instruction to the student. Many DI teachers fundamentally disagree with constructivism and believe that trained and informed teaching professionals make the best choices regarding what and how their students need to learn.

2. No, Howard Gardner did not invent DI. The theory of multiple intelligences has lost favor over the last few years. No brain scientist has yet found a “musical intelligence” section in the cerebral cortex. Many teachers who differentiate instruction do believe that students who haven’t yet learned certain skills need to be taught differently, but not necessarily because those students lacked a particular form of “intelligence” and, instead, need to learn via another of the seven intelligences.

3.Learning styles, multi-sensory instruction, and the importance of environmental preferences are long-standing educational constructs. All are based upon minimal research. Still popular with special education teachers, learning style inventories do not provide reliable diagnostics about how to differentiate instruction. Auditory and visual processing deficits can be diagnosed, but no research has yet demonstrated which instructional strategies work best for these learners.

Instructional Strategies

4. Some teachers and administrators reject DI because of the mistaken belief that DI rejects direct instruction. Nothing could be further from the truth. Much of DI instruction involves direct, explicit instruction as in pre-teaching concepts and/or skills or direct whole class instruction followed by small group and/or individual review.

5.A commonly held belief is that there is only one way to differentiate instruction and that is through small groups: heterogeneous cooperative groups or homogeneous ability groups. Small groups are certainly key DI instructional strategies, but not the only ones.

6. Many veteran teachers or special education teachers think that DI means individualized instruction. Some picture SRA® reading kits with color-coded reading comprehension cards and individual students anxiously lining up to have their work corrected by the teacher to see if they will advance to the “silver” level. Some DI teachers do individualize instruction, but many prefer other instructional methods.

7. Some teachers equate DI with open-ended assignments that focus on self-exploration, based upon student choice, such as with some components of Learning Centers or Writers Workshop. Some assume that DI classrooms are Montessori®-style “open classrooms” with self-guided, unstructured learning. Students only learn when the task is perceived as being meaningful or relevant. In other words, the curriculum is defined by the student. Actually, most successful DI teachers are excellent classroom managers, are extremely organized, and are very much in charge of student learning and the curricular content. DI classrooms may be student-centered, but they are very much teacher-directed.

8.Some have heard that problem solving, critical thinking, inquiry learning, and “big picture” learning are key features of a DI classroom. Some see visions of classrooms plastered with Bloom’s Taxonomy and Costa’s Levels of Questioning posters. Good differentiated instruction challenges students of all levels at all levels of thinking, but these characteristics and/or instructional methodologies are not exclusive to a DI classroom.

9. Interdisciplinary thematic instruction is not joined at the hip with DI. The flexibility and cross-over potential of this instructional approach may lend itself to DI strategies, but there is no necessary connection in the way that some advocates insist.

10. The authentic assessments movement has no hand-in-glove connection with DI. Some teachers who differentiate instruction do use authentic assessments; some do not. DI does not necessitate varying assessments according to the preference and/or perceived needs of individual students.

11.Many think that the “basics” are ignored in a DI classroom. Some have heard that only whole-to-part, deductive reasoning and learning are emphasized. Nothing could be further from the truth. Much of differentiated instruction is skill-centered and inductively builds knowledge through layers of learning from basic to more complex, from part-to-whole.

12.Many teachers believe that DI requires different instruction, different assessments, different grading, and different assignments for different students. Actually, most DI teachers use the same instructional methodologies, the same assessments, the same grading system, and many of the same assignments for all of their students. Teachers may emphasize different instructional components, but many of the tools are the same for all students.

Who Receives Differentiated Instruction

13.“DI is only for students with learning disabilities,” some say. “Every child must have an Individualized Education Program (IEP) and teachers are held accountable for adapting their instruction to the prescribed needs of each student. Response to Intervention (RTI) is all about the procedures to ensure that these IEPs are enforced.” Not true. Although “mainstreaming” or “full inclusion” models have placed students with identified (IEP) learning disabilities or special needs students back into the classroom, DI is not just for these students. DI is for every student.

14.“DI is only for heterogeneously mixed classes, not for tracked programs including remedial (intervention), regular, and accelerated (honors) divisions.” One of most ubiquitous beliefs about DI is the erroneous assumption that it is only intended for diverse classrooms. Although many teachers who practice DI fundamentally disagree with tracking, differentiated instruction deals with meeting the needs of individual students, not groups, per se. Thus, many teachers practice DI in very homogeneous settings.

15.“DI is forced upon teachers to meet the needs of Gifted and Talented Education (GATE) students in order to qualify for state funding.” There may be isolated situations in which teachers are required to differentiate instruction because they have identified gifted students in their classes; however, this would certainly be the exception, not the rule.

Curricular Rigor and Fairness

16.Advocates of DI may be surprised to hear that many think that DI eliminates standardized curriculum and cannot be standards-based. Actually, DI can be used to “catch up,” “keep up,” and “move ahead” students in reference to grade-level standards. In fact, teachers practicing DI usually reference their diagnostic and formative assessments to an established instructional scope and sequence, based upon state standards.

17. Some teachers, parents, and administrators think that DI “dumbs-down” the level of classroom instruction because kind-hearted teachers are loathe to “leave any child behind” and will slow the pace of instruction or adjust curriculum accordingly to ensure “success for all.” Actually, DI teachers tend to focus more on individual mastery of established objectives and less on whole-class mastery. Teachers who do not practice DI are more likely to “teach to the center,” in terms of the academic abilities of their students.

18.Many teachers believe that DI “pigeon-holes” students and lowers their self-esteem. Because DI does involve frequent diagnostic and formative assessment to adjust instruction to the needs of the learners, students become well-aware of their relative strengths and weaknesses in given academic areas. Instructional practices, such as flexible ability grouping, can contribute to this potential problem. However, sensitive and well-trained teachers need not succumb to creating negative self-concepts in their classrooms. And, pretending that students do not have different abilities and levels of skills mastery will not increase self-esteem. Improved self-concept, at least in part, derives from increasing expertise and reaching individual goals—exactly the instructional foci of differentiated instruction. Instead of lowering expectations by ignoring individual differences, DI raises expectations for individual students.

19.Some think that DI is inherently undemocratic. They say that the bright students or students with a strong work ethic get extra work or open-ended assignments to keep them busy while “freeing up” the teacher to spend more of her time addressing the needs of underperforming students, who get “modified” assignments, i.e. less work than “regular” or “accelerated” students. Or, worse yet, the bright students are recruited as peer tutors. Thus, industriousness is rewarded with more work and laziness is rewarded with less work. And grading is adjusted as the capstone to these foundational inequities. There may be some truth to this myth in many DI classrooms. The over-arching issue of fairness and how fairness is applied within the walls of the classroom reflect teachers’ personal political and pedagogical philosophies. Some, for example, would argue that it is inherently unfair that students are ill-prepared for their grade-level instruction through no fault of their own.

20.Students who are the beneficiaries of DI won’t be able to compete in the real world. Students not used to working to the highest standards will be ill prepared for gateway tests, such as the SAT® and ACT®. If students aren’t exposed to challenging, high-level skills and concepts, they will be doomed to failure. Actually, DI teachers try to bridge the gap between basic and advanced skills and concepts. They design instruction to help students “keep up” while “catching up.”

Teacher Commitment

21.Some teachers resist DI because they wrongly perceive that managing diverse instructional strategies and on-going assessments takes a genius. However, teachers of all ability and experience levels can begin differentiated instruction with proper training and support. Furthermore, DI is not an “all or nothing” proposition. Most teachers layer in different aspects of DI over years of instruction.

22.Some say that DI requires way too much preparation, assessment, correction, and record-keeping. This may have been a truism years ago, but clever teachers have since developed effective short-cuts to planning, assessment, and paper work. DI need not be a cause of teacher “burn-out.”

23.Some proponents of DI intimate that differentiated instruction solves all educational problems and ensures student mastery of key concepts and skills. However, you “can lead a horse to water, but you can’t always make him drink.” Some students exposed to the best DI will continue to fail.

Teaching the Language Strand also has the resources to meet the needs of diverse learners. Diagnostic grammar, usage, mechanics, and spelling assessments provide the data to enable teachers to individualize instruction with targeted worksheets. Each remedial worksheet (over 200 per program) includes independent practice and a brief formative assessment. Students CATCH Up on previous unmastered Standards while they KEEP UP with current grade-level Standards. Check out PREVIEW THE TEACHER’S GUIDE AND STUDENT WORKBOOK to see samples of these comprehensive instructional components. Check out the entire instructional scope and sequence, aligned to the Grades 4-8 Common Core Standards.

Hey Mark — You have some great insights here. Thanks for posting all this. I need to correct a couple of things, however, regarding your first differentiation myth above. You wrote, “…Constructivism is an educational philosophy predicated on the belief that learning occurs best when students construct their own “rules,” “mental models,” and “meaning-making” to integrate new experiences into their existing schemata and prior knowledge. As applied to differentiated instruction, constructivists including the likes of Carol Ann Tomlinson, Amy Benjamin, and Rick Wormeli, believe that students should be provided multiple options for taking in information and making sense of ideas and that teachers must adapt the curriculum or mode of instruction to the student. Many DI teachers fundamentally disagree with constructivism and believe that trained and informed teaching professionals make the best choices regarding what and how their students need to learn.”

>>> Thanks for putting me, Amy, and Carol into the constructivists camp. There’s a lot of merit to that approach, and teachers who claim not be constructivist often provide very constructivist experiences, even within their direct instruction approach. All three of us, however, do not declare, “Constructivism above all.” We’re much more pragmatists — Whatever works to increase the learning over that which could otherwise be achieved. Constructivism is one of many learning models differentiating teachers can incorporate in their classrooms to make sure students learn.

In addition, you wrote that trained, informed professionals — as if they were in contrast to constructivist teachers — make the best decisions regarding how and what students learn. You’re right about teachers being in charge of students’ learning, but no constructivist teacher operates blind to society expectations, i.e. the curriculum, and those trained professionals have to be informed about the individual students they teach so they can make those decisions. That last thing we need is the teacher who laminates his lesson plan after teaching it once 25 years ago. All DI teachers are assessment-focused, gathering information so they can make informed decisions how best to proceed with their students. If a student has no background with a particular term we’re using in the lesson, for example, we pause and explain the background to that student so the lesson can continue and the student is successful with the content. I may or may not have used a constructivist methodology to explain this term, but this is not turning the curriculum over to the student. This is using what I know about the student to make sure the student understands and can learn. Constructivism as used by differentiated teachers is not anyhwere close to diminishing the curriculum or not being professional and teacher directed.

The way you wrote your blog makes it sound like many differentiated instruction teachers disagree with giving students multiple ways of taking in and processing information and adapting curriculum or instruction to the student. I work with thousands of teachers face-to-face, in their schools, on-line, in conferences, via e-mail, etc. and I have yet to find one differentiating teacher or expert who actually disagrees as you say so many do. Nobody disputes the need to be creative if our first instructional approach doesn’t work. Is that yielding control of the curriculum to the student? No. It’s not a weak strategy to do this; it’s making sure the student learns the material.

There are so many times that a student fails to learn something because he didn’t understand the analogy the teacher was using and would benefit from interaction with the teacher as they found a new one, or if the teacher guided him as he fit physical pieces together with manipulatives on his desk so he could see the larger algorithm or principle at work. Why would we take this option away from differentiating teachers by saying they arent’ really done in a differentiated classroom? The differentiating teacher is all about increasing his repertoire of responses, not closing them off.

Finally, while it’s nice to be included in the group of constructivist-minded educators, it’s false to claim these is all Amy, Carol, and I advocate. Constructivism is one of many tools at our disposal, but it’s not the only tool, nor do most differentiated teachers push back against it’s use.

Everything else in your blog seems right on target from my perspective, and worth getting out there. Thanks for taking the time to compose and post it. Hopefully it will start some great conversations.

Items 13 through 15 reflects a key point that DI is for every student, from those who struggle to the gifted learners.

Items 16 and 17 points out that DI done effectively is based on curriculum standards. Therefore, learners are developing skills and concepts with support and depth through differentiation.

Items 21 through 23 notes that while DI planning takes work and time, as one becomes proficient that time is better used. Start where you feel comfortable, and incorporate what makes clear sense. Like our students, we must learn at the rate and pace that fits our needs.

Item 18 illustrates how important is student’s affective in learning. Frustration can be healthy, but failure is a confidence destroyer. That’s not to say, we protect kids from failure. Rather through interventions and careful planning based on assessments, we should be able to guide learners along their course so that failure is avoided. If failure occurs, help the student learn from it and be prepared to help repair their confidence to move forward. Consider the impact of a healthy vs. toxic workplace. Such environments effect worker efficiency. For students, the classroom is their work place.

The other “Myths” addressed in Mark’s article contain some over the top messages by using “absolute” language as to what DI is or is not. Taken to extreme, his arguments may seem logical. But people and learning are not absolutes, with many shades of color.

Put simply, Differentiated Instruction is planning instruction that addresses where student skills stand.
–Formative assessment data tells us when and where to differentiate.
–Learning styles data informs us of the various way learners may connect to the concepts. I remind myself that even with the best laid plans, when students find their entry point it may or may not be based on what I set up.
List of tools: http://wb4all.blogspot.com/2010/01/relationships-matter-next-steps.html

–DI is not a silver bullet to solving all learning problems. There are no guarantees. BUT, DI has a strong impact on learners–much more so than the traditional approach of teaching the same way to everyone, which is more convenient to the teacher than the learner.
–DI done effectively occurs in many pedagogical approaches. What makes constructivism appealing is that students are active partners in teaching and learning.

Also consider:
–http://wb4all.blogspot.com/2009/12/relationships-matter-pt-1-layers-of.html

Regardless of the approach you use, DI success, and good instruction in general, occurs consistently if we ask 3 questions in the planning process:

1. What do students need to know, understand, and be able to do? (Learning Targets)

2. How will students show what they know, and don’t know? (Formative and summative assessments that lead to the learning targets)

3. How will we support the students who struggle? And how will we support the students who already know the learning target?

Thanks for responding. I think you misread the trained and informed reference. Read the context again and I think you’ll see that these teacher qualities are contrasted with kids making the content and process choices, not constructivist teachers. My point is that teachers need to be the ones making informed choices about how to differentiate instruction, not students. Student choice re: content and process is at best “the blind leading the blind.” I do agree with your practical emphasis on what works, as long as the teacher sets the agenda.

Thanks for posting a link to your article. I found it very useful in reaffirming that there must not be a one “right” way to implement DI. I am still wrestling with what that will look like in my classroom.

Thanks for your comment on my blog about DI. I followed your link to here and enjoyed what I read. I concur and wish to point out that I was speaking about DI as I use it and see it working in a computer classroom in which I have been teaching since 1983. Many of your points speak directly to me in my classroom esp #16, 19, and 23. I have seen how the computer has allowed me to provide an environment in which all my scholars find their own level and helps esp with #23 when I can show the work of classmates as I hope to salt the fodder they ingest requiring the consumption of water. i have found the computer classroom helps me with all aspects of teaching the basics as well as being sensitive to each scholar’s learning style is respected and used in hir favor.

I love these 23 points and agree with the theory as my practice has demonstrated in a computer classroom utilizing DI and practical theory.

Thanks for clarifying, Mark. I think there’s still room for a student’s sense of what he needs to learn to help teachers orchestrate the learning experience. For example, a student might claim that flash cards don’t really help him learn vocabulary so much as a another strategy does, and he’d like to use this other strategy. He asks the teacher about using this other strategy, and effective teachers usually say, “Let me get out of your way and let you learn.” If we’re not teaching the process itself, it doesn’t matter how students learn it, as long as they learn it well. We don’t want to limit students to our imagination. Students have important insights into their own learning that our curriculum and student overload doesn’t always allow us to see. This does not change the teacher’s agenda, and it would be a mistake to summarily dismiss such input from our thinking as we teach. Does this fit with your sense of differentiation?

Thanks again for posting all this. It sure helps the conversation to have something substantive on which to chew! — Rick Wormeli

@Rick Wormeli
This conversation is great for getting into the nuances of learning. Students are such an important part of the equation.
Rick,
I’m appreciative of the important point you make:
“He asks the teacher about using this other strategy, and effective teachers usually say, “Let me get out of your way and let you learn.” If we’re not teaching the process itself, it doesn’t matter how students learn it, as long as they learn it well. We don’t want to limit students to our imagination.”
I might have to share this quote with the schools I work with in Michigan. What ever pedagogical approach teachers choose to use need to be mindful that learning and achievement begins with the student–both in readiness and perspective. We educators need to be flexible and willing to involve student voice in the instructional conversation.

Getting out of the way does not mean the teacher is marginalized. Quite the opposite. The structures and frameworks are developed with expertise and experience, while “listening” to students’ voices. A skillful and thoughtful educator can accomplish this. Even more effective is when teachers collaborate towards this end–that’s another conversation.

John — Your comments are right on target, but that’s a big mindset for teachers and administrators. It seems like the most successful teachers see the enterprise of teaching/learning as a collaboration with students, not something done unto them. This mindset affects not only how we interact with students, but also how we plan and evaluate learning experiences. One of the most important tools we have as educators is doubt. The teacher reflects: Do I really know that the author meant to symbolize man’s quest for immortality in this one part of the novel, or am I quoting what someone else fed me long ago when I was student? Is this the only way there is to teach graphing inequalities? Is this lesson working with all students or only a subset? A little healthy doubt once in while keeps us humble and alert, both of which serve students better than one-size-fits-all, my-way-or-the-highway approaches. I recognize that most teachers don’t set out to do the one-size approach; they’re conscientious people. Many move there, however, out of survival, cynicism (sp?), pressures from colleagues or above, or because they never paid attention to their creative selves. Some teachers who figuratively (or literally) throw up their hands and declare, “There’s just no other way to teach this,” are really saying, “I’ve exhausted my imagination.” In these moments, they need to surround themselves with outside the box thinkers and catalysts. Paying attention to the intellectual/innovative life of teachers is one of the great gifts we can gift today’s students. — Rick Wormeli

As a staff developer and district reading specialist for five years in Elk Grove Unified (the third largest school district in California), I had the opportunity to visit countless elementary classrooms. Student-choice learning including “Learning Centers,” “Free-Choice Fridays,” unsupervised “SSR” (student selected books with no accountability), “Learning Style” assignments in which kinesthetic learners acted out, rather than wrote essays, “Multiple Intelligences Learning” in which students could choose to create a written report, oral report, a song/rap, or create a model… I could go on… were prominent features of most classrooms. Not only was a substantial portion of the daily content in the hands of students, teachers also devolved the methods of learning to their students via student choice. Reading test scores hovered in the 40th percentiles for years, especially in the middle and lower SES schools.

Enter a swing in the pendulum and a return to phonics-based instruction with Open Court® reading: a scripted instructional block and “workshop” in which reading instruction was differentiated according to formative data. Most teachers hated the tightly-bound curriculum and, especially, the organized “workshop.” No teacher choice there and no student choice, either. Reading Scores jumped within two years in the same demographic to the 60th percentiles and have remained there for a dozen years. The what of instruction mattered, but the how of instruction mattered more. Most of us credited the differentiated instruction of Open Court® “workshop” as the key factor.

Beyond that elementary experience, I’ve taught eleven years at the middle school level, eight at the high school level, and three at the community college level. From my own teaching experience, and more appropriately the learning experiences of my students, I’ve gleaned a few morsels about student learning. A nine-year-old, twelve-year-old, sixteen-year-old, and twenty-year-old all share a few common developmental learning characteristics: First, most would take the path of least resistance to reach their goals. Few are mature enough to include learning skills and concepts as key components of these personal goals. Students want the grades and the related self-satisfaction; they want access to the next class and/or school; they want to keep their parents off of their backs–they are human. We were once as they are. Understanding their characteristics should inform our “teaching/learning… collaboration with students.” Second, they don’t know what they don’t know and they don’t know how to best learn what they don’t know. How could they? If they did know the how, they would already know the what, especially if what was perceived as relevant to their immediate wants and needs.

Now, I’m not a stuffy autocrat who says “My way or the highway” and, of course, there is always another imaginative “way to teach this.” Sure, some choice can increase student motivation and “one-size fits all” ways to problem-solve or learn a concept or skill may not get the job done for some students; however, even these choices are most efficiently and effectively teacher-driven and modeled. For example, in composition, some students prefer to draft first and revise thereafter; others prefer to integrate the drafting and revision process. Teacher modeling, such as “teacher think-alouds” and guided practice in the two options are the most effective means to teach these choices. Students learn which option or combination thereof works best for them through teacher direction, not from a sink or swim, work it out yourself, trial and error process. Far from “getting out of the way and letting them learn,” teachers need to actively direct both the what and how of the learning process.

I am much more concerned about the what, than the how, in terms of differentiated instruction. If teachers buy-in to data-driven instruction, based upon diagnostic and formative assessments, the battle is chiefly won and DI is an easy sell. However, most teachers aren’t there yet, and until they get there, the how of instruction is a relatively fruitless pursuit. When more teachers get there, we can continue the “skirmishing” re: student choice and the how of effective instruction and learning.

This thread is a timely resource that I plan to use with new teachers in our district as part of a staff development day in which we will address both DI and UbD. It will provide these new teachers with a dialogue about DI philosophy, application, and strategies. It also let’s them see how difficult it can be to reach consensus when we fail to read the comments of others with an open mind and instead become defensive. Be careful guys. Well-reasoned student choice is an important part of learning and is a skill that we can’t assume students have – it needs to be modeled and taught like any other important skill. I find it hard to imagine a good teacher leaving a student totally in a “sink or swim, work it out yourself, trial and error process.” There are times that it helps to step back and let them struggle, but it would be with a watchful eye and a way to scaffold the student.

No, I didn’t–a nicely balanced article, I think. Only one recommendation causes me pause: “Respond to individual student differences (such as learning style, prior knowledge, interests, and level of engagement).” Of course, we have to respond to prior knowledge–that we can objectively measure and teach to… the others are pure bunk: Learning style has been thoroughly debunked; interests moves to student choice issue, and I’m not sure what is meant by “level of engagement.”

Differentiated Instruction is the latest educational philosophy
to sprout wings and take the great self serving mantra of the
desk bound pedagogically clueless academician. Every child gets instruction based on individual interest, learning preference,
learning style, readiness level, ability, preferred mode of learning
and thats just to start. Wow, what planet are they from! I am one
teacher with 27 students and you want all that plus a cup of tea. Differentiated Instruction sounds like a wonderful Orwellian lie designed to keep teachers bouncing around like pinballs doing senseless retort with all students suffering mediocrity. I have a very simple educational philosophy “Teach to the TOP” and drag everyones learning style along for the ride! Individual interest, learning preference, learning style, readiness level, ability, preferred mode of learning is moot if you can not read! I teach ALL students to read and reason without excuses or exceptions. What data has been submitted to the WWC that proves this philosophy has efficacy?
门门懂,样样瘟 (“All trades known, all trades dull”)
三脚猫 (“A cat with only 3 legs”)
万宝全书缺只角 (“樣樣通,樣樣鬆 (“All trades known, all trades dull”)
An encyclopedia with one corner missing”)
周身刀,無張利 (“Surrounded by knives, none are sharp”)
El que mucho abarca poco aprieta (“Who embraces too much, has a weak grasp”).
Aprendiz de todo, maestro de nada (“Apprentice of everything, master of nothing”).
Un océano de conocimiento de una pulgada de profundidad (“An ocean of knowledge of an inch deep”).
A todo le tiras, y a nada le pegas (“You shoot for everything, but you hit nothing”).
همه‌کاره و هیچ‌کاره (“One tries to do everything, but is capable of doing nothing”).Πολυτεχνίτης και ερημοσπίτης (“He who knows a lot of crafts lives in an empty house”).

Love the quotes, Sean. While I agree that those who advocate the hows of differentiated instruction (learning styles, multiple intelligences, and others) carry things too far with little, if any research justification, let’s not throw the baby out with the bath water. Certainly we need to set high expectations and teach with rigor. However, teaching to the top begs the question. Are we teaching to the what or to the whom? My thought is that we should do both. Let’s keep up and catch up. Teaching to effective diagnostic data will pinpoint the whats and address the needs of the individual whoms. All good research (and practice) defines, isolates, and controls the variables. The best teachers are, indeed, research practitioners.